L Bloomfield1,2,A Burroughs3, A Beswick2, A Bowen4, R McCann2, P Armstrong2
1Edith Cowan University, School of Medical and Health Sciences, Joondalup Dr, Joondalup WA 6027
2WA Department of Health, Communicable Disease Control Directorate, 189 Royal St East Perth WA 6004
3Australian National University, Master of Applied Epidemiology Scholar, Canberra ACT 0200
4Telethon Kids Institute, Hospital Ave, Nedlands WA 6009
There has been a sharp increase of community-associated methicillin-resistant Staphylococcus aureus (CA-MRSA) reported in Western Australia (WA). A primary driver of this increase has been the proliferation of a single clone ‘Queensland CA-MRSA’, particularly within the Kimberley region. A study was conducted to quantify the burden of this increase on healthcare facilities.
Data linkage was performed by the WA Data Linkage Brank using MRSA notifications, hospitalisation and emergency department presentation data, using probabilistic linkage methods. Specimens received from residents with a Kimberley postcode, received between 1 July 2003 and 30 June 2015 were eligible for linkage. CA-MRSA cases were associated with hospital admission were designated as such if they were diagnosed with 48 hours of admission.
Annual notifications of CA-MRSA from Kimberley residents increased from 63 in 2003/04 to 1,454 in 2014/15. In total, 1,251 notified cases were admitted to hospital and 2,265 presented to an emergency department. Of these, 87% of hospitalisations and 74% of emergency presentations were designated to be ‘CA-MRSA related’, based on ICD-10 codes. On average, 19% of all CA-MRSA notifications each year were admitted to hospital with a ‘CA-MRSA related’ diagnosis. The median length of stay was 3 days. Almost two-thirds of CA-MRSA related skin or soft tissue infections required aspiration and/or excision, incision or drainage.
The increasing number of CA-MRSA cases is related to an increasing burden on healthcare facilities in terms of occupied bed-days, procedures and ED management. Further work is required to curtail this organism in the community.